As of late March 2023, it will no longer be possible to make purchases in Nintendo eShop for Wii U and Nintendo 3DS family systems, including add-on content.
For more details, please see here.

Super Smash Bros. (Title Pending) for Nintendo Switch
Nintendo Direct
Add-on Content Smashes In!
DOWNLOADABLE FIGHTERS
update Bayonetta
update Corrin

Warning! Spoilers Inside!
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GameCube Controller Adapter for Wii U

Launch: 29/11/2014

This is a peripheral which will allow you to use Nintendo GameCube controllers with Super Smash Bros. for Wii U. (Wii U console, software and Nintendo GameCube controllers sold separately.)

You can connect up to four Nintendo GameCube controllers using the GameCube Controller Adapter for Wii U. The peripheral plugs into the Wii U console with two USB cables – you can use either the USB ports in the front or rear of the console.

You can use your existing Nintendo GameCube controllers to enjoy Super Smash Bros. for Wii U with the same feeling of control as Super Smash Bros. Melee and Super Smash Bros. Brawl.

The Nintendo GameCube Controller – Super Smash Bros. Edition shown is also planned for release on the same day.